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Drink 2 Litres of Water a Day Myth

Water is actually our most essential nutrient, so one might expect that advice on something as basic as how much water we should drink each day and when would be fairly simple and clear. However, most of what we are told about water and how much we should drink seems to be complete mythology. And indeed, many people really believe in fairy tales such as ‘drink two litres of water a day’ myth.

Myth number one is probably the belief that we should all drink 2 litres of water a day. You will not need to search for too long to find this particular piece of nutritional nonsense. It is simply mandatory that any recommendation for a healthy diet worth mentioning includes the advice to drink two litres of water a day. This is obviously pure liquid gold for the water bottling industry, which has shot from zero to a multi-billion dollar global industry in the last forty years. And they certainly do their bit to perpetuate the fairy tale that we would be much better off if we were drinking more water and ideally from one of their overpriced bottles.

And so it often happens that such beliefs get engraved in our minds to the extent that it does not even cross our mind to question them. But the whole two litres of water a day rule is total and utter myth, with not a drop of evidence to support it. The fact is that we can meet our fluid requirements perfectly well from many other beverages other than plain water, such as drinking juice, tea, coffee and milk, bearing in mind that food also contributes a substantial amount to our fluid intake. Thus, we do not need plain water at all to stay hydrated if we are getting enough fluid from these other sources.

Myth number two is the flawed advice that coffee and tea are diuretics, causing dehydration, meaning we have to drink extra water to compensate for the loss. We must have heard it a zillion times. It is often claimed by respected “experts” that for every cup of coffee we drink, we should get two glasses of water to prevent dehydration of our body. It is total fiction. For those who are used to drinking them, caffeinated beverages like coffee and tea count perfectly well toward their fluid intake. For those who never drink them and suddenly get a large amount of caffeinated drinks, the caffeine will have a diuretic effect. But it is just a temporary effect. If we keep drinking coffee, the body quickly adapts, so that the caffeine ceases to have its dehydrating effect. The result is that caffeinated drinks hydrate the body just as well as any other beverage.

And this is not all. Popular wisdom tells us over and over again that drinking more water will hydrate and moisturise our skin, rejuvenate our complexion and help improve conditions such as acne or probably the most classic myth of all to flush toxins from the body and skin. It goes without saying that there is not a scrap of scientific evidence to support any of it.